EMS

Blood and Tissue Storage Monitoring: Beyond the Temperature Reading

Author: Gagan Kaur

Sep 15, 2026

Blood and tissue organizations manage materials that are often limited, time-sensitive, and difficult or impossible to replace. Maintaining appropriate storage conditions is essential, but protecting these materials requires more than checking the number displayed on a refrigerator or freezer.

A strong monitoring strategy considers how conditions are measured, how quickly changes are detected, who receives an alarm, what happens next, and whether the organization can reconstruct the event afterward. It should also account for risks outside the storage unit, including power loss, water intrusion, communication failures, and changes in the surrounding environment.

Regulations and industry standards reinforce the need for controlled storage, suitable equipment, records, quality systems, and defined procedures. In the United States, organizations may need to consider applicable requirements in 21 CFR Part 606 for blood and blood components and 21 CFR Part 1271 for human cells, tissues, and cellular and tissue-based products. The exact requirements differ according to the material, process, accrediting body, and jurisdiction. Each organization must translate those requirements into a monitoring program that fits its own operations and risk profile.

Start with the material, not the monitoring device

An effective strategy begins by identifying what is being protected and what could affect its suitability. Blood components, human cells, tissues, tissue-based products, reagents, and patient or donor samples may have different storage specifications and operational risks.

For each material or process, consider:

The required storage conditions
The acceptable operating range and established alarm limits
How quickly an excursion could affect the material
Whether the material can be moved to backup storage
How much time personnel have to respond
What records are needed to evaluate an excursion
Which internal procedures, regulations, and accreditation standards apply

This risk-based review helps determine what should be monitored, where sensors should be placed, how often readings should be recorded, and how alarms should escalate. It also helps distinguish a meaningful monitoring program from a collection of devices that may not work together when a problem occurs.

Look beyond temperature

Temperature is usually the first condition considered in blood and tissue storage, but it is not always the only risk. Depending on the application and facility, a more complete strategy may include:

Humidity: Relevant for certain processing, laboratory, storage, or ambient environments
Liquid nitrogen levels: Important for cryogenic storage systems
Differential pressure: Used in controlled areas where airflow direction and separation matter
Water detection: Helpful near storage equipment, condensate lines, pipes, mechanical spaces, and other potential leak sources
Power status: Provides early notice when a circuit, outlet, or piece of equipment loses power
Door position: Helps identify a door that has been left open or is not sealing properly
Equipment alarm contacts: Allows an independent monitoring system to receive an alarm generated by the equipment
Communication status: Identifies when a sensor, transmitter, network connection, or other system component stops reporting

Not every facility needs every type of monitoring. The goal is to identify conditions that could affect stored materials, interrupt operations, or delay the response to an emerging problem.

Consider the area surrounding the storage equipment

Monitoring plans often focus on conditions inside refrigerators, freezers, incubators, and cryogenic storage units. The room surrounding that equipment can also create risk.

For example, an HVAC problem may raise the ambient temperature and force several freezers to work harder at the same time. A leaking pipe or condensate line can threaten equipment, electrical connections, or access to the room. A facility power event can affect multiple storage units even if each unit initially remains within range.

Monitoring ambient temperature, water, power, and other facility conditions can provide earlier warning of a problem that may eventually affect several assets. This broader view is especially valuable in rooms containing a high concentration of critical equipment.

Treat alarm response as part of the monitoring system

Detecting an out-of-range condition is only the beginning. The monitoring program must also deliver useful information to people who are prepared to respond.

Organizations should define:

Who receives the first notification
How and when the alarm escalates
Who is responsible during nights, weekends, and holidays
How recipients acknowledge an alarm
What actions personnel should take
When quality, facilities, laboratory, or clinical leadership should be involved
How the alarm, response, and final disposition are documented

Contact lists should be reviewed regularly. Personnel change roles, phone numbers change, departments reorganize, and on-call responsibilities shift. An escalation path that was correct a year ago may no longer reach the right people.

Alarm testing is equally important. A program should verify the complete path from detection through notification and response, not simply confirm that a sensor produces a reading. Testing can reveal expired contact information, notification gaps, unclear ownership, or dependencies that were not apparent during routine operation.

Understand the limits of manual checks

Manual checks remain part of many blood and tissue operations. They can provide a documented observation at a specific moment and may be required by an organization's procedures. However, a manual reading represents only the time at which it was taken.

Conditions can change between scheduled checks. A unit may drift out of range, recover, and appear normal by the time of the next reading. Continuous monitoring provides visibility into what happened between observations and can notify personnel while the condition is developing.

This does not mean automated monitoring eliminates the need for human review. Personnel still need to evaluate trends, investigate alarms, document actions, and determine whether stored materials were affected. Technology provides the record and the warning; trained personnel provide the judgment and response.

Keep calibration, mapping, and monitoring distinct

Calibration, temperature mapping, and continuous monitoring are related, but they answer different questions.

Calibrationevaluates whether a measuring device is producing accurate readings when compared with a traceable reference standard. It supports confidence in the measurement itself.

Temperature mapping evaluates how temperature is distributed throughout a storage unit or controlled space under defined conditions. It can identify hot spots, cold spots, recovery behavior, and locations that may not be represented by a single display reading.

Continuous monitoring tracks conditions over time and can notify designated personnel when established limits are exceeded.

One activity does not automatically replace the others. A calibrated sensor may be accurate at its location without demonstrating temperature uniformity throughout the chamber. A mapping study characterizes performance during a defined period but does not provide ongoing alarms. Continuous monitoring provides ongoing data but depends on appropriate sensor selection, placement, maintenance, and calibration.

Plan for failures in the monitoring pathway

A monitoring strategy should consider what happens when a component other than the storage unit fails. Questions to address include:

What happens if the network becomes unavailable?
How will personnel know that a sensor has stopped communicating?
Is monitoring data retained during an interruption?
Are notifications dependent on a single communication method?
Is backup power available for critical monitoring components?
Can authorized personnel reach the system remotely when appropriate?
Is there a documented contingency process?

These questions help organizations evaluate the complete monitoring pathway, from the sensor to the person responsible for taking action.

Review the program as operations change

Monitoring programs should not remain static while facilities, equipment, and personnel change around them. A periodic system health check can identify gaps before they become visible during an excursion, audit, or emergency.

A review should consider whether:

New equipment, rooms, or departments have been added
Decommissioned assets and former users have been removed
Alarm limits and delays remain appropriate
Contact lists and escalation paths are current
Sensors are properly located and within their calibration period
Reports still provide the information users need
Recurring alarms or service issues indicate a larger problem
Manual steps could introduce delays or transcription errors
Software versions and system components remain supported
Planned renovations or expansions will change monitoring requirements

This review should bring together the people who use and support the system, which may include quality, laboratory operations, blood bank or tissue bank leadership, facilities, information technology, and service personnel. Each group sees different risks, and the strongest monitoring programs reflect those perspectives. Organizations should also review the current requirements and guidance issued by their applicable authorities and accrediting bodies, including the AATB Standards for Tissue Banking and relevant AABB standards and accreditation resources.

A stronger monitoring strategy supports a stronger response

The value of environmental monitoring is not limited to collecting readings. A well-designed program helps an organization recognize a developing problem, reach the correct people, respond according to procedure, and produce a clear record of the event.

Rees Scientific works with blood centers and tissue banks, hospitals, and other regulated organizations to monitor critical environments and equipment. The Rees Monitoring System uses a broad range of environmental monitoring sensors to monitor temperature and other important conditions while supporting alarm notification, data access, and reporting. Rees Scientific also provides calibration, mapping, qualification, and ongoing service options to help organizations maintain their monitoring programs over time.

The right approach should reflect the materials being protected, the facility in which they are stored, and the procedures governing the operation. Whether an organization is reviewing an existing system or planning a new facility, the starting point should always be a clear understanding of risk. Organizations evaluating their current approach can request an environmental monitoring assessment to identify equipment, facility conditions, and alarm-response needs that should be considered.

Frequently Asked Questions

1. Is continuous monitoring required for every blood or tissue storage application?

Requirements depend on the material, activity, jurisdiction, accreditation program, and the organization's own procedures. FDA regulations and industry standards establish expectations for appropriate storage, equipment, records, and quality controls, but organizations must determine how those expectations apply to each operation. Applicable regulations, current AATB or AABB standards, manufacturer instructions, and internal quality requirements should be reviewed before defining a monitoring approach.

2. Can the temperature display on a refrigerator or freezer serve as the monitoring record?

An equipment display shows the unit's current reading, but it may not provide an independent, continuous record or notify personnel when no one is present. Organizations should evaluate how the temperature is measured, where the probe is located, whether data are retained, and how an excursion triggers a response.

3. How often should alarm contacts and escalation procedures be reviewed?

They should be reviewed on a defined schedule and whenever personnel, responsibilities, phone numbers, facilities, or procedures change. Organizations should also test the alarm pathway periodically to verify that alerts reach the correct people and that recipients understand the required response.

4. What is the difference between a spot water sensor and rope water detection?

A spot sensor detects water at a specific location. Rope or cable-style detection can cover a longer path, such as the perimeter of equipment or an area beneath pipes and condensate lines. Selection should be based on the likely source of water, the area requiring coverage, drainage patterns, and the potential effect of a leak.

5. When should a blood or tissue organization conduct a monitoring-system health check?

A review should occur periodically and after meaningful changes such as adding equipment, expanding a facility, changing personnel, updating software, experiencing repeated alarms, or discovering a gap during an audit or event investigation. The review should examine sensors, calibration status, alarm limits, users, contacts, reports, communication pathways, support status, and contingency procedures.

Is Your Blood or Tissue Storage Monitoring Strategy Complete?

A monitoring program should do more than record temperature. It should help your organization identify risks, notify the right people, and respond with confidence when conditions change.

Rees Scientific can help you evaluate your storage equipment, monitored conditions, alarm procedures, and potential coverage gaps.

Request an Environmental Monitoring Assessment

Editorial reference links

https://reesscientific.com/request-an-assessment

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